Energy generation and storage has long been a subject of study and development. Of special importance is the storage of electrical energy in a compact form that can be easily charged and discharged, such as rechargeable batteries and/or electrochemical capacitors. High power, especially high current pulse, rechargeable electrochemical storage devices are very important in applications using electrical pulses such as communications and power tools. In these devices, high electrochemical kinetic rate, long cycle life of the electrode, and good ionic conductivity of the electrolyte are extremely important.
Most high-power electrochemical energy storage devices utilize aqueous electrolytes, since the aqueous electrolytes are known to have the highest ionic conductivity. However aqueous electrolytes also result in problems when handling and packaging the devices. Furthermore, some good high-power electrochemical energy storage devices such as nickel/zinc (Ni-Zn), and silver/zinc (Ag-Zn) batteries do not have good cycle life due to dendrite growth on the zinc anode. The growth of dendrites on the zinc anode causes short circuits that significantly reduce the cycle life of the battery and is a severe limitation of the conventional art.
Since a zinc anode can provide a very negative anodic potential compared to other materials, it would be highly desirable to provide an electrochemical energy storage device utilizing zinc anodes that did not suffer from the poor cycle life due to dendritic growth. Elimination of this phenomena would enable one to create a device having increased charged storage capacity, thus further enabling the miniaturization of energy storage devices.